Ratchet for screw-drivers or drills



(No Model.) Z. T. PURBISH. RATGHET FOR SCREW DRIVERS 0R DRILLS.

No. 537,681. .Paten'tedApr. 16, 1895.

Ewe raoz NITE rArns ZAOHRY T. FUR'BISH, on AUGUSTA, MAINE.

RATCHET FOR SCREW-DRIVERS OR DRILLS.

SPECIFICATION forming part of Letters Patent No. 537,681, dated April 16, 1895.

Application filed January 24:, 1895- To aZZ whom it may concern:

Be it known that I, ZAGHRY T. FURBISH, a citizen of the United States of America, residing at Augusta, in the county of Kennebec and State of Maine, have invented certain new and useful Improvements in Ratchets for Screw-Drivers or Drills, of which the following is a specification.

My invention is an improved ratchet device for imparting rotary motion to a spindle, which may form the shank or socket stem of a screw driver or drill, or any similar instrument requiring reversible rotary movement.

My invention is particularly designed'for a convertible tool, which may be used either as a screw driver or drill, but is not necessarily limited to this particular tool. It is illustrated in the accompanying drawings, in which- Figure 1 shows the invention as applied to a shank or stem of a hand-implement adapted to carry a rotary tool, such as a screw driver or drill. Fig. 2 shows a side elevation of the ratchet device with its shell or case partly removed. Figs. 3 and 4: are respectively sections on lines y-y and x-a; of Fig. 1. Fig. 5 is a longitudinal section of parts of the ratchet detached. Fig. 6 represents the locking device of the ratchet detached.

In the drawings A represents the tubular shank of the tool handle of which B is the head. Fixed to this shank is a case 0 located near its lower end and having a chamber in line with the bore of the tube. Through this chamber and into the bore of the tube a spindle D is arranged to slide freely. The spindle is threaded either by grooves or ribs in reverse directions. I have shown reverse grooves 1 and 2 symmetrically arranged and reversed to each other. The interior of the case 0 is open above and below, as shown in Figs. 1 and 2, and also in Figs. 3 and 4, by means of slots 4. and 5. The case is solid on each side and the chamber is cylindrical excepting at the slotted points and there are cavities on each side of the solid portions as shown at 6 and 7 in Figs. 3 and 4. Within the case is located a ratchet mechanism E, which is shown in Fig. 2 more plainly. This comprises two rollers or sleeves 10-11 provided with grooves 8 extending across them longitudinally of the tool, which grooves in Serial No. 536,157. (No model.)

-both rollers are arranged to be in line with each other. Each roller is adapted to turn freely in the case, and each is provided with a rib 20 Fig. 5 to engage the grooves in the spindle, one rib being inclined reversely from the incline of the other. Between the grooved rollers and surrounding the spindle is the ring 9 which is held against rotation by frictional. contact withthe sides of the case. This ring may be grooved above and below in line with the slots 4 and 5 as at 21 Fig. 5, these grooves having the same shape as those in the sleeves, so that when in line therewith, it forms a continuous channel, in which the dog may be shifted, or without the groove it may slide over the ring, in which case the ring is of such diameter that its periphery comes only 'to the bottom of the grooves 8.

In Fig. 1 the rollers are shown in dotted lines and the roller or sleeve 10 being shown with its section of the casein Fig. 3, and roller or sleeve 11 with its section of the case in Fi 4.

That which I call for convenience, the upper slot in Fig. 3, has one Wall (left-hand) curved or undercut, While the right-hand wall is straight. The lower slot on the other side of the case has the right-hand wall curved or undercut, while the left-hand wall is straight,

straight sides of the slotsis reversed, the upper slot being curved on the right hand side and the lower on the left. The curved or undercut part of the groove forms'a binding surface for the dog, and it will be observed that there is a pair or set of these binding surfaces on each side, and that the binding surfaces of each set are oppositely arranged to each other, and also that the sets on opposite sides are arranged reversely to each other.

The dogging or binding piece is shown in Fig. 6, somewhat enlarged in comparison with the other figures. It consists of a bit of steel rod made cylindrical and just fitted to the grooves in the sleeve. Preferably the ends breadth of the ring 9, so that it may lie in the groove in that ring without engaging with the grooves in either sleeve. One of these cylindrical pieces is inserted in the slot on each side.

The case is 'providedon each side with a cover 12 between which and the solid portions, is a shallow chamber 6 and 7. The covers are slotted in line with the slots in the solid portion of the case, and an elastic holding device 14, provided with a stud 15, is placed over each dog when it is in place, the stud projecting through the slot in the cover, while the ends of the holding device project in over the ends of the dog, so that it can be slipped longitudinally of the ratchet device. Now when the dog is upon the roller or sleeve 10, for example, and the sleeve is rotated to p in which the sleeves are located, slots in said case each having at each end a reversely located undercut wall and a vertical wall opthe left or the case turned to the right (looking at Fig. 3) the dog will bind in the curve or undercut face of the slot, but will turn freely in reverse movement against the vertical wall of the slot on the opposite side. If the dog be slipped to engage the groove of the sleeve 11 the action will be the reverse with the samerotary movements of the sleeveor case; but if the dog be left on the ring, it will be totally inactive. Both sides of the case are provided with this ratchet apparatus in the particulars above described, and the result is. that if the: dog on one. side be left upon the ring, the apparatus may be used as a screwdriver by simply manipulating the dog on the other side only, to: give a rotary or left hand movement according as it is desired to turn the screw in or out. The dog being set upon sleeve 10, for example, which holds the sleeve in one direction, the operator grasping the tool and forcing the tube A downward upon the spindle D- will cause the spindle to turn by reason of its I engagement with the inclined rib 20 on the interior surface of the sleeve, which engage with the thread 1 of the spindle. dogs are in engagement one with the sleeve 10 and the other with the sleeve 11 Fig. 2,

then both up and down movements of the tube A on the spindle D will turn the tool in the same direction. The relative arrangement in presence of two witnesses.

of the ribs 20 in the grooved parts 10 and 11 is shown in Fig. 5. Thus the implement is adapted to be used either as a screw driver or drill according as one or the other is secured in the socket F of the end of the spindle D.

While I have shown my invention embod- When both.

Having thus described my invention, what I claim is 1. In combination with a spindle having double or reversed threads, sleeves having ribs engaging therewith, and each havinglongitudinal grooves on its outer surface, a case posite the undercut wall, and each slot being the reverse of the other in respect of its undercut and vertical walls; and shifting cylindrical dogs or clutches, substantially as def scribed.

2. In combination, the tubular shank A, the case fixed thereto and having a slot on each side with the walls at each end of each slot reversely undercut, sleeves having grooves and the intermediate ring 9, adapted to hold the sleeves in position in the case and a shifting cylindrical dog adapted to act in connection with the grooves and the undercut sur- 2 face of the slot and a spindle reversely threaded and engaging with the interior of the sleeves, substantially as described.

3. In combination, the reversely threaded spindle, the casing and the ratchet mechanism comprising the two rotary ratchets each having a rib or projection to engage the reversely inclined grooves and locking means adapted to hold each ratchet against rotation in either direction, or to allow either ratchet .to be free or to hold both at the same time against rotation in one direction, substantially as described.

In testimony whereof I affix my signature ZAGHRY T. FURBISH.

Witnesses:

HENRY E. COOPER, R. E. OuBAND. 

